This invention relates to a novel copolymer and a process for producing the same, and more particularly, to a novel copolymer which is excellent in heat resistance and capable of having its heat resistance controlled, and good in mechanical strength, solvent resistance and flame resistance and also excellent in mechanical properties, particularly in elongation and impact strength compared to the conventional cyanoaryl ether polymer, and to a process for producing the same.
There are disclosed a polycyanoaryl ether having various structures in Japanese Laid-Open Patent Publication No. 14270/1972. However, there is a disadvantage that these polycyanoaryl ethers are insufficient in heat resistance.
Further, in Japanese Laid-Open Patent Publication No. 206433/1984, there is disclosed a cyanoaryl ether polymer obtained by dihalogenobenzonitrile and hydroquinone or biphenol as starting materials. While this polymer is excellent in mechanical strength and heat resistance, its heat resistance cannot be freely controlled and thus it has disadvantage that it cannot flexibly cope with various requests in the various fields of use. Further, such a polymer is not necessarily sufficient in view of characteristics such as mechanical characteristics required for raw materials of electronics and electrical devices or mechanical parts. Accordingly, it has earnestly been desired to develop a cyanoaryl ether polymer having excellent mechanical characteristics compared to that of the conventional one.